Progressive macular hypomelanosis: an epidemiological study of 103 cases in Southeast Brazil

Introduction: Progressive macular hypomelanosis is characterized by the emergence of hypopigmentation, predominantly in the trunk region of young women of mixed racial origin. Although recent studies suggest that Propionibacterium acnes may have an important role in the pathogenesis, its etiology remains unclear. Objective: To evaluate the prevalence of the condition with regards to gender, age, skin phototype, affected areas and disease onset, and the relationship with ordinary acne and oily skin in the city of Niterói, Rio de Janeiro State, in the coastal region of Southeast Brazil. Methods: Retrospective epidemiological study that uses the analysis of medical records of 103 patients with diagnosis of progressive macular hypomelanosis, from 2001 to 2012. Results: Eighty-two percent of studied patients were women and 18% men, with a predominance of phototypes III (42.7%) and IV (42.7%). The average age of onset of the disease at diagnosis was 26 years. In 46.0% of patients the disease duration ranged from 1 to 4 years. When two areas were affected (50%), the dorsum was the most frequent (79.0%), followed by the abdomen (20.0%). In 98% of cases, patients had oily skin, and 71.8% had active acne. Conclusion: Progressive macular hypomelanosis is a chronic condition that primarily affects the skin of the dorsum and abdomen of young women with skin phototypes III and IV, who are also bearers of oily skin and acne. There are still many doubts regarding the true etiology and treatment of progressive macular hypomelanosis. The high percentage of association with skin oiliness and acne vulgaris suggests that these clinical conditions are possibly related.

Keywords: HYOPIGMENTATION; EPIDEMIOLOGY; ACNE VULGARIS